Teeth transplanted between mice that are matched for the major histocompatibility complex (MHC) but who differ by non-MHC antigens elicit immune responses that may promote their own survival. The purpose of this research is to identify the role played by cellular and/or humoral factors in the permanent survival of teeth transplanted between mice disparate for 1 or 2 non-MHC loci. In addition, we hope to demonstrate that teeth transplanted across a multiple non-MHC barrier elicit graft-protective immunity and that this immune state is associated with long term graft survival. Teeth will be transplanted to heterotopic and orthotopic sites in recipient mice who differ by 1, 2, or several non-H-2 antigens. Control animals will receive skin grafts or allotransplants of bone. Recipients will be studied for cellular and humoral cytotoxicity and for cell-mediated and antibody-mediated suppression of immunity in vitro and in vivo. Survival of tooth allografts will be confirmed by routine histological procedures.